Progressive interstitial lung disease in hypomyopathic dermatomyositis in the COVID-19 pandemic: A case report.

BACKGROUND: Clinically amyopathic dermatomyositis (CADM) is characterized by typical skin lesions with no (amyopathic) or subclinical (hypomyopathic) evidence of muscle involvement. Patients with CADM may also develop rapidly progressive interstitial lung disease (ILD), and have a poor prognosis. However, the diagnosis of rapidly progressive ILD faces a challenge during the severe acute respiratory syndrome coronavirus 2 pandemic. Severe acute respiratory syndrome and ground-glass attenuation on a chest computed tomography scan are the presenting features in both conditions. CASE PRESENTATION: A 45-year-old woman with amyopathic dermatomyositis had acute onset of fever and dyspnea in February 2020. She had abnormal lung findings on CT scan. Polymerase chain reaction testing for SARS-CoV-2 was not available at that time. Chest CT revealed non-specific manifestations that could be either the signs of ILD or SARS-CoV-2 infection. Antiviral therapy was initiated with oseltamivir. Three days later, she had erythema on face, palm, and back. The ratio of lactate dehydrogenase (LDH) isoenzyme 3 to total LDH was elevated. The ratio of LDH isoenzyme 1 to total LDH was declined. Therefore, she was transferred to the rheumatology ward for further treatment. However, she died from respiratory failure 2 weeks later. CONCLUSIONS: We speculate that the altered LDH isoenzyme pattern may be an early biomarker for co-occurrence of CADM and ILD.

Complement in autoimmune inflammatory myopathies, the role of myositis-associated antibodies, COVID-19 associations, and muscle amyloid deposits.

INTRODUCTION: The inflammatory myopathies (IM) have now evolved into distinct subsets requiring clarification about their immunopathogenesis to guide applications of targeted therapies. AREAS COVERED: Immunohistopathologic criteria of IM with a focus on complement, anti-complement therapeutics, and other biologic immunotherapies. The COVID19-triggered muscle autoimmunity along with the correct interpretation of muscle amyloid deposits is discussed. EXPERT OPINION: The IM, unjustifiably referred as idiopathic, comprise Dermatomyositis (DM), Necrotizing Autoimmune Myositis (NAM), Anti-synthetase syndrome-overlap myositis (Anti-SS-OM), and Inclusion-Body-Myositis (IBM). In DM, complement activation with MAC-mediated endomysial microvascular destruction and perifascicular atrophy is the fundamental process, while innate immunity activation factors, INF1 and MxA, sense and secondarily enhance inflammation. Complement participates in muscle fiber necrosis from any cause and may facilitate muscle-fiber necrosis in NAM but seems unlikely that myositis-associated antibodies participate in complement-fixing. Accordingly, anti-complement therapeutics should be prioritized for DM. SARS-CoV-2 can potentially trigger muscle autoimmunity, but systematic studies are needed as the reported autopsy findings are not clinically relevant. In IBM, tiny amyloid deposits within muscle fibers are enhanced by inflammatory mediators contributing to myodegeneration; in contrast, spotty amyloid deposits in the endomysial connective tissue do not represent 'amyloid myopathy' but only have diagnostic value for amyloidosis due to any cause.

Dermatomyositis Following BNT162b2 mRNA COVID-19 Vaccination.

Dermatomyositis (DM) is one of the uncommon multi-organ idiopathic inflammatory myopathies that has been reported following the hepatitis B, Influenza, tetanus toxoid, H1N1, and BCG vaccines. However, an association with the coronavirus disease 2019 (COVID-19) vaccine is yet to be reported. In this case, we present the case of a 43-year-old Asian Indian female who was diagnosed with DM 10 days after receiving the second dosage of BNT162b2 mRNA COVID-19 vaccination, in the absence of any additional triggering factors. The diagnosis was established based on physical examination, serological antibodies, magnetic resonance imaging of the muscles, skin biopsy, and electromyography. She received standard treatment for DM, including oral high doses of prednisolone, hydroxychloroquine, mycophenolate, and physiotherapy. The treatment successfully reversed skin changes and muscle weakness. This is the first reported case of classic DM complicated by interstitial lung disease following COVID-19 vaccination. More clinical and functional studies are needed to elucidate this association. Clinicians should be aware of this unexpected adverse event following COVID-19 vaccination and arrange for appropriate management.

Understanding and managing anti-MDA 5 dermatomyositis, including potential COVID-19 mimicry.

Anti-Melanoma Differentiation-Associated gene 5 (MDA-5) Dermatomyositis (MDA5, DM) is a recently identified subtype of myositis characteristically associated with Rapidly Progressive Interstitial Lung Disease (RP-ILD) and unique cutaneous features. We reviewed PubMed, SCOPUS and Web of Science databases and selected 87 relevant articles after screening 1485 search results, aiming to gain a better understanding of the pathophysiology, clinical features, diagnosis, and treatment approaches of anti-MDA-5 DM described in the literature. The etiopathogenesis is speculatively linked to an unidentified viral trigger on the background of genetic predisposition culminating in an acquired type I interferonopathy. The clinical phenotype is highly varied in different ethnicities, with new clinical features having been recently described, expanding the spectrum of cases that should raise the suspicion of anti-MDA-5 DM. Unfortunately, the diagnosis is frequently missed despite excessive mortality, calling for wider awareness of suspect symptoms. RP ILD is the major determinant of survival, treatment being largely based on observational studies with recent insights into aggressive combined immunosuppression at the outset.

COVID-19 or clinical amyopathic dermatomyositis associated rapidly progressive interstitial lung disease? A case report.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has reach pandemic proportions globally. For patients with symptoms of fever and cough accompanied by rapid lung damage progression, COVID-19 needs to be distinguished from interstitial lung disease (ILD) attributed to connective tissue disease (CTD), especially dermatomyositis (DM)/clinical amyopathic dermatomyositis (CADM) associated rapidly progressive interstitial lung disease (RP-ILD). CASE PRESENTATION: We report a case of a woman observed with fever, cough, and rapid lung damage during the epidemic. The patient had a suspicious epidemiological history, and her chest CT scans showed lung damage similar to that caused by COVID-19, but anti-Ro52 antibody was strongly positive. She was diagnosed with CADM associated RP-ILD and died 1 month later. CONCLUSIONS: During the COVID-19 epidemic, it is critical to carefully assess patients with CTD related ILD, especially RP-ILD associated with CADM. Repeated nucleic acid tests for COVID-19 are necessary to achieve accurate case diagnosis. High-resolution CT (HRCT) of the chest is presently deemed an inefficient technique to distinguishing between COVID-19 and CADM associated RP-ILD. The characteristic rashes of dermatomyositis require careful observation and can often provide diagnostic clues. For patients with CADM, a high titers of anti-Ro52 antibody may be related to the pathogenesis of RP-ILD, suggesting a poor prognosis.